﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Text.RegularExpressions;
using System.IO;
using System.Net;
using System.Text;
using System.Security.Cryptography.X509Certificates;
using System.Net.Security;
using System.Security.Cryptography;

/// <summary>
///Util 的摘要说明
/// </summary>
public class Util
{
    /// <summary>
    /// 给TOP请求签名 API v2.0
    /// </summary>
    /// <param name="parameters">所有字符型的TOP请求参数</param>
    /// <param name="secret">签名密钥</param>
    /// <returns>签名</returns>
    protected static string CreateSign(IDictionary<string, string> parameters, string secret)
    {
        parameters.Remove("sign");

        IDictionary<string, string> sortedParams = new SortedDictionary<string, string>(parameters);
        IEnumerator<KeyValuePair<string, string>> dem = sortedParams.GetEnumerator();

        StringBuilder query = new StringBuilder(secret);
        while (dem.MoveNext())
        {
            string key = dem.Current.Key;
            string value = dem.Current.Value;
            if (!string.IsNullOrEmpty(key) && !string.IsNullOrEmpty(value))
            {
                query.Append(key).Append(value);
            }
        }
        query.Append(secret);

        MD5 md5 = MD5.Create();
        byte[] bytes = md5.ComputeHash(Encoding.UTF8.GetBytes(query.ToString()));

        StringBuilder result = new StringBuilder();
        for (int i = 0; i < bytes.Length; i++)
        {
            string hex = bytes[i].ToString("X");
            if (hex.Length == 1)
            {
                result.Append("0");
            }
            result.Append(hex);
        }

        return result.ToString();
    }


    /// <summary>
    /// 组装普通文本请求参数。
    /// </summary>
    /// <param name="parameters">Key-Value形式请求参数字典</param>
    /// <returns>URL编码后的请求数据</returns>
    protected static string PostData(IDictionary<string, string> parameters)
    {
        StringBuilder postData = new StringBuilder();
        bool hasParam = false;

        IEnumerator<KeyValuePair<string, string>> dem = parameters.GetEnumerator();
        while (dem.MoveNext())
        {
            string name = dem.Current.Key;
            string value = dem.Current.Value;
            // 忽略参数名或参数值为空的参数
            if (!string.IsNullOrEmpty(name) && !string.IsNullOrEmpty(value))
            {
                if (hasParam)
                {
                    postData.Append("&");
                }

                postData.Append(name);
                postData.Append("=");
                postData.Append(Uri.EscapeDataString(value));
                hasParam = true;
            }
        }

        return postData.ToString();
    }

    private static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
    {
        return true; //总是接受  
    }

    public static string Post(string url, IDictionary<string, string> param, Version httpversion)
    {
        string result = string.Empty;

        #region ---- 完成 HTTP POST 请求----

        HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
        req.Method = "POST";
        req.KeepAlive = true;
        req.Timeout = 300000;
        req.ContentType = "application/x-www-form-urlencoded;charset=utf-8";

        ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);

        req.ProtocolVersion = httpversion;
        byte[] postData = Encoding.UTF8.GetBytes(PostData(param));
        Stream reqStream = req.GetRequestStream();
        reqStream.Write(postData, 0, postData.Length);
        reqStream.Close();
        HttpWebResponse rsp = (HttpWebResponse)req.GetResponse();
        Encoding encoding = Encoding.GetEncoding(rsp.CharacterSet);
        Stream stream = null;
        StreamReader reader = null;
        stream = rsp.GetResponseStream();
        reader = new StreamReader(stream, encoding);
        result = reader.ReadToEnd();
        if (reader != null) reader.Close();
        if (stream != null) stream.Close();
        if (rsp != null) rsp.Close();
        #endregion
        return Regex.Replace(result, @"[\x00-\x08\x0b-\x0c\x0e-\x1f]", "");
    }

    /// <summary>
    /// TOP API POST 请求
    /// </summary>
    /// <param name="url">请求容器URL</param>
    /// <param name="appkey">AppKey</param>
    /// <param name="appSecret">AppSecret</param>
    /// <param name="method">API接口方法名</param>
    /// <param name="session">调用私有的sessionkey</param>
    /// <param name="param">请求参数</param>
    /// <returns>返回字符串</returns>
    public static string Post(string url, string appkey, string appSecret, string method, string session,

    IDictionary<string, string> param)
    {

        #region -----API系统参数----

        param.Add("app_key", appkey);
        param.Add("method", method);
        param.Add("session", session);
        param.Add("timestamp", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
        param.Add("format", "xml");
        param.Add("v", "2.0");
        param.Add("sign_method", "md5");
        param.Add("sign", CreateSign(param, appSecret));

        #endregion

        string result = string.Empty;

        #region ---- 完成 HTTP POST 请求----

        HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
        req.Method = "POST";
        req.KeepAlive = true;
        req.Timeout = 300000;
        req.ContentType = "application/x-www-form-urlencoded;charset=utf-8";
        byte[] postData = Encoding.UTF8.GetBytes(PostData(param));
        Stream reqStream = req.GetRequestStream();
        reqStream.Write(postData, 0, postData.Length);
        reqStream.Close();
        HttpWebResponse rsp = (HttpWebResponse)req.GetResponse();
        Encoding encoding = Encoding.GetEncoding(rsp.CharacterSet);
        Stream stream = null;
        StreamReader reader = null;
        stream = rsp.GetResponseStream();
        reader = new StreamReader(stream, encoding);
        result = reader.ReadToEnd();
        if (reader != null) reader.Close();
        if (stream != null) stream.Close();
        if (rsp != null) rsp.Close();
        #endregion
        return Regex.Replace(result, @"[\x00-\x08\x0b-\x0c\x0e-\x1f]", "");
    }
}